What forecasters said that day
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Milwaukee, WI wrote its last area forecast discussion before the first event at Apr 13, 7:09 PM CST, 3 hours 35 minutes earlier. Its key messages:
- Strong to severe storms are still expected late this evening into tonight. All severe hazards possible as well as flash flooding.
- Heavy rain this evening and tonight with the storms resulting in localized higher rainfall exceeding 1-3 inches. Thus a Flood Watch is in effect for counties north of I-94 tonight. Also expected rises on area rivers and cresting above flooding stage with the additional rainfall.
- Additional windows for heavy rainfall, flooding, and thunderstorms Tuesday and Wednesday and again later this week.
Area forecast discussion, Apr 13, 7:09 PM CST, 3 hours 35 minutes before
Area Forecast Discussion...UPDATED
National Weather Service Milwaukee/Sullivan WI
809 PM CDT Mon Apr 13 2026
.KEY MESSAGES...
- Strong to severe storms are still expected late this evening
into tonight. All severe hazards possible as well as flash
flooding.
- Heavy rain this evening and tonight with the storms resulting
in localized higher rainfall exceeding 1-3 inches. Thus a
Flood Watch is in effect for counties north of I-94 tonight.
Also expected rises on area rivers and cresting above flooding
stage with the additional rainfall.
- Additional windows for heavy rainfall, flooding, and
thunderstorms Tuesday and Wednesday and again later this
week.
&&
.UPDATE...
Issued 809 PM CDT Mon Apr 13 2026
Tonight:
Well organized 925-700 mb warm, moist advection and frontogenesis
is supporting severe convection from north central IA and srn MN
ewd across central WI. The sly 925-850 mb jet of 40-50 kt will
actually increase MLCAPE to 1500-2000 J/KG across all of srn WI
this evening ahead of the sfc low that will track from wrn IA to
ne IA and se MN by 06Z. CAMs suggest the developing MCS north of
La Crosse will move esewd across central WI, while another MCS
will form across se MN into sw WI. The 2nd MCS will then track to
the right of the mean wind (esewd around 35-40 kt) across much of
srn WI. 0-3km shear is 250 degrees around 40 kts and oriented
mostly parallel to the expected MCS, but any short north to south
line segments would have the potential for QLCS tornadoes. Overall
though the main threat is damaging winds. 05-06Z is a good
estimate from Fond du Lac to Madison then 07-08Z into the MKE
metro area.
Gehring
&&
.SHORT TERM...
Issued 234 PM CDT Mon Apr 13 2026
Tonight through Wednesday:
Continue to see a very active spring pattern today through
Wednesday across southern WI. Strong to severe thunderstorm
environment will set up across the area each day varying in
location and strength. Will also see heavy rainfall associated
with this activity and widespread 1-3 inches possible through
the middle of the week, but localized higher rainfall greater
than forecast will be possible contributing to flooding impacts.
First opportunity for severe and flooding potential will be
later today/tonight. Will be another window on Tuesday, which
has the better potential for more widespread severe activity
over the CWA. Then another window will occur on Wednesday, but
will be a bit more uncertain as it depends on what happen today
and tomorrow.
Rest of this Afternoon:
MCV has stayed south more into IL and produced a couple perky
thunderstorms. However, the cap is holding across southern WI
this afternoon and anything that is trying grow upscale is not
making it at this time. Will continue to monitor, but the better
chances for development will be later this evening.
This Evening into Tonight:
Environment still looking primed for convection across central
WI with a warm front strewn across the central part of the state
as a surface low over NE lifts eastward. In the warm sector
south of the main boundary over southern WI seeing SBCAPE
exceeding 1000 J/kg and looking to increase toward 1500 J/kg or
more through the remainder of afternoon. Paired steep lapse
rates around 7-8C/km, dewpoints already in the 60s, and deep
layer shear +45kt all will support development through the
evening.
The bulk of the severe and flooding activity is looking to
develop early this evening through tonight generally along and
around the warm front boundary toward the northern half of the
CWA (generally north of I-94) as the nose of 40-55kt LLJ noses
into WI. Still looking to see a few discrete development along
the warm front back in west central WI early this evening where
the instability and deep layer shear align with the LLJ. All
severe hazards will be possible for discrete development south
of the warm front and cannot rule a tornado or two as 0-1km SRH
increased to around 200 m2/s2. Might see a few discrete sneak
into our northwest, but majority of it looks to remain just
outside our CWA. However given the easterly flow parallel to
the frontal boundary expect to see this activity gradually merge
and cluster more into a linear structure through the evening.
This will transition the severe threat more toward wind and
flooding. The 12z CAMs continue to trend toward a more southern
shift in this activity and looking to impact our northern tier
of counties through tonight. While damaging winds will be the
primary severe threat, the convection training over the same
area and producing locally higher amounts exceeding 1-3 inches
over saturated soils may leading to localized flash flooding as
well as rises on area rivers. Thus have issued a Flood Watch
for the areas with the greatest concerns tonight.
Expect this cluster to works its way along the boundary
overnight with a bulk of the models having it move off and
weaken after midnight through early Tuesday morning.
Tuesday- Tuesday Night:
Another window for severe weather expected for Tuesday. Overall
looks to be a bit better set up for southern WI as the front
from today's activity is progged to be draped across our area.
The main question will be where will the boundary set up as
depending which side of the boundary you are on will dictate
the severe impacts. We are beginning to see a trend with the
frontal boundary bisecting our CWA on the global models as well
as on the 12z HREF. If this continues, looking at the better
severe potential to be favored toward the southern portion of
the CWA.
Wherever the front sets up, expect areas along and north of the
warm front to be more susceptible to large hail threat as
instability will be more elevated north of the surface boundary.
Looking at MUCAPE between 1000-2000 J/kg along and north of the
boundary paired with the +40kt deep layer shear. While areas
along and south of the boundary will be capable of producing
more damaging winds and cannot rule out even a few tornadoes in
addition to hail. More favorable surface based instability with
+1500 J/kg of SBCAPE aligning with the deep layer shear in the
warm sector. CAMs also are pinging on increasing low-level SRH
exceeding 150-200 m2/s2 supportive of a tornado or two.
Storm mode evolution also looks similar to toady as well with
convective initiation being more discrete/isolated convection
which will be more supportive of supercells and tornado, but
CAMs prog this activity to cluster and merge through the
evening and thus transitioning to more of a damaging wind and
embedded tornado threat.
Lastly given saturate grounds and previous days rainfall any
heavier rainfall moving over the same area will be susceptible
to flash flooding as well as rises on area river above flood
stage.
Again there will be limited upper-level synoptic forcing for
Tuesday activity and mainly be driving by low-level WAA, LLJ,
warm frontal boundary, as well as localized mesoscale lift from
upstream MCV or remnant outflow from today's convection. So
will continue to monitor the hi-ress models guidance through
this evening to have a better picture of where things set up.
Wednesday:
The active spring pattern continues for Wednesday as well.
Again still need to see how things pan out Tuesday for exact
locations of this activity. However, seeing more upper-level
support with the Wednesday round as an upper-level shortwave
trough digs across the Plains and lifts over the region. While
more favorable upper-level synoptic forcing will be present, the
overall surface low track continues to trend over southern WI.
This will set up the a frontal boundary more across southern
portions of the area, but could see additional shifts.
Nevertheless there will be another opportunity for heavy
rainfall and severe potential along this system. Will continue
to monitor and see if current trends hold or if things shift.
Wagner
&&
.LONG TERM...
Issued 234 PM CDT Mon Apr 13 2026
Thursday through Monday:
Finally get a bit of a break in this active pattern on Thursday
as an upper-level ridge builds into the region. However, this
looks to be short lived as an upper-level trough begins to
deepen across the northern Plains and gradually lift into the
upper Midwest later Friday into Saturday. The associated surface
low looks to track up the Upper Mississippi River Valley during
this time which will place southern WI in the warm sector.
Again looking at environment that will support increased shower
and thunderstorm activity. Given the current pattern and track,
will need to keep an eye on strong to severe potential for our
western portions of the CWA, but the latest trends in the models
has this system a bit slower, thus the better environment looks
to be further west. Will continue to monitor and see if this
trend continues for this late week system.
Behind this late week system, the pattern looks to settle down
as the trough pushes into the eastern CONUS while an upper-level
ridge looks to build Sunday through the start of next week.
Expect mainly drier and mild conditions at this time through
this period.
Wagner
&&
.AVIATION...
Issued 809 PM CDT Mon Apr 13 2026
A line of thunderstorms, potentially severe at times, is
expected to drop southeast through southern Wisconsin from
roughly 05Z to 09Z tonight. Low level wind shear is likely this
evening into tonight ahead of the thunderstorms. Lower ceilings
(1500 to 3000 ft) and visibilities (2-5 miles) are anticipated
as the line of storms move through.
A few storms may linger towards daybreak early tomorrow, with
dry weather likely through the morning hours. Low clouds may
take a good chunk of the morning to improve to VFR. Generally
south to southwest winds are expected tomorrow, though a few
models do show winds may turn onshore tomorrow near the lake by
late morning.
Another round of thunderstorms is expected tomorrow by late
afternoon or early evening, with the potential for severe
storms once again.
DDV
&&
.MARINE...
Issued 234 PM CDT Mon Apr 13 2026
An active heavy rainfall and thunderstorm pattern is expected
across the region this afternoon through Wednesday. Will see
frontal boundaries stall across the lake at various location
each day with increase thunderstorm activity focused along and
around it as well. Overall winds are looking fairly light and
may contribute to periods of fog over the open waters. Winds
will vary depending on where the fronts set up. Portions of the
lake south of the boundaries will see predominantly southerly
winds, while more easterly winds are expected north of the
boundary. Will see a break in shower and thunderstorm activity
for Thursday, but active pattern returns for the end of the week
into Saturday.
Wagner
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...Flood Watch...WIZ046-WIZ047-WIZ051-WIZ052-WIZ056-WIZ057-WIZ058-
WIZ059-WIZ060 until 7 AM Tuesday.
LM...Dense Fog Advisory...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 until 7 AM Tuesday.
&&
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www.youtube.com/NWSMilwaukeeHazardous weather outlook, Apr 13, 8:09 PM CST, 2 hours 35 minutes before
Hazardous Weather Outlook...UPDATED
National Weather Service Milwaukee/Sullivan WI
909 PM CDT Mon Apr 13 2026
WIZ046-047-051-052-056>060-062>072-150215-
Marquette-Green Lake-Fond du Lac-Sheboygan-Sauk-Columbia-Dodge-
Washington-Ozaukee-Iowa-Dane-Jefferson-Waukesha-Milwaukee-
Lafayette-Green-Rock-Walworth-Racine-Kenosha-
909 PM CDT Mon Apr 13 2026
This Hazardous Weather Outlook is for portions of east central
Wisconsin, south central Wisconsin and southeast Wisconsin.
.DAY ONE...Tonight
Strong to severe thunderstorms possible late evening into tonight.
Heavy rain and flooding potential will also be possible,
especially across central WI.
A Flood Watch is in effect for portions of east central and south
central Wisconsin through Tuesday morning.
.DAYS TWO THROUGH SEVEN...Tuesday through Monday
Additional rounds of thunderstorms Tuesday through the end of the
week. Heavy rain and flooding potential will accompanying this
activity. Also will be strong to severe thunderstorm chances
Tuesday afternoon through Wednesday and again toward the end of
the week.
.SPOTTER INFORMATION STATEMENT...
Spotter activation may be needed this afternoon/evening across
the central WI and will be needed areawide Tuesday and Wednesday.
LMZ643>646-150215-
Sheboygan to Port Washington WI-
Port Washington to North Point Light WI-
North Point Light to Wind Point WI-
Wind Point WI to Winthrop Harbor IL-
909 PM CDT Mon Apr 13 2026
This Hazardous Weather Outlook is for the nearshore waters from
Sheboygan Wisconsin to Winthrop Harbor Illinois.
.DAY ONE...Tonight
Areas of dense fog possible through tonight.
Chances for thunderstorms tonight, with some strong to severe
storms possible.
.DAYS TWO THROUGH SEVEN...Tuesday through Monday
Chances for thunderstorms continue through the end of the week,
with some strong to severe storms possible.
Areas of fog are possible into Tuesday morning. Some fog could
become dense.
LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868-
870-872-874-876-878-150215-
Lake Michigan Michigan City IN to St. Joseph MI 5 NM offshore to
mid-line of lake.-
Lake Michigan from Seul Choix Point to Rock Island Passage 5NM
offshore to Mid Lake-
Lake Michigan South of a line from Seul Choix Point to the
Mackinac Bridge and North of a line from Charlevoix MI to South
Fox Island 5NM offshore-
Lake Michigan from Charlevoix to Point Betsie MI 5NM Offshore to
mid lake-
Lake Michigan from Point Betsie to Manistee MI 5NM offshore to
Mid Lake-
Lake Michigan from Rock Island Passage to Sturgeon Bay WI 5NM
offshore to mid lake-
Lake Michigan from Sturgeon Bay to Two Rivers WI 5NM offshore to
Mid Lake-
Lake Michigan from Two Rivers to Sheboygan WI 5NM offshore to Mid
Lake-
Lake Michigan from Sheboygan to Port Washington WI 5NM offshore
to Mid Lake-
Lake Michigan from Port Washington to North Point Light WI 5NM
offshore to Mid Lake-
Lake Michigan from North Point Light to Wind Point WI 5NM
offshore to Mid Lake-
Lake Michigan from Wind Point WI to Winthrop Harbor IL 5NM
offshore to Mid Lake-
Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5NM
offshore to Mid Lake-
Lake Michigan from Wilmette Harbor to Michigan City in 5NM
offshore to Mid Lake-
Lake Michigan from Pentwater to Manistee MI 5NM offshore to Mid
Lake-
Lake Michigan from Whitehall to Pentwater MI 5NM offshore to Mid
Lake-
Lake Michigan from Grand Haven to Whitehall MI 5NM offshore to
Mid Lake-
Lake Michigan from Holland to Grand Haven MI 5NM offshore to Mid
Lake-
Lake Michigan from South Haven to Holland MI 5NM offshore to Mid
lake-
Lake Michigan from St Joseph to South Haven MI 5NM offshore to
Mid Lake-
909 PM CDT Mon Apr 13 2026
This Hazardous Weather Outlook is for the open waters of Lake
Michigan.
.DAY ONE...Tonight
Areas of dense fog will possible tonight, particularly across the
northern 3/4 of the lake where a Dense Fog Advisory is in effect.
Chances for thunderstorms late this evening into tonight, some
strong to severe storms possible.
.DAYS TWO THROUGH SEVEN...Tuesday through Monday
Chances for thunderstorms continue through the end of the week,
some strong to severe storms possible.
Areas of fog could continue through Tuesday morning. Some fog
could become dense.
www.weather.gov/mkx
In the hours before
Local storm report, Apr 13, 4:49 PM CST, 5 hours 55 minutes before
Preliminary Local Storm Report
National Weather Service Milwaukee/Sullivan WI
549 PM CDT Mon Apr 13 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0409 PM Hail Portage 43.54N 89.46W
04/13/2026 E0.88 Inch Columbia WI Public
&&
MGSpecial weather statement, Apr 13, 9:59 PM CST, 45 minutes before
Special Weather Statement
National Weather Service Milwaukee/Sullivan WI
1059 PM CDT Mon Apr 13 2026
WIZ046-047-051-140500-
Green Lake WI-Marquette WI-Fond Du Lac WI-
1059 PM CDT Mon Apr 13 2026
...STRONG THUNDERSTORMS WILL IMPACT NORTHWESTERN FOND DU LAC...GREEN
LAKE AND MARQUETTE COUNTIES THROUGH MIDNIGHT CDT...
At 1059 PM CDT, Doppler radar was tracking a cluster of strong
thunderstorms near Princeton, or 12 miles south of Wautoma, moving
northeast at 25 mph.
HAZARD...Wind gusts up to 40 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Ripon, Berlin, Montello, Markesan, Westfield, Princeton, Rosendale,
Green Lake, Brandon, Lawrence, Eldorado, Packwaukee, Mecan, Oxford,
Neshkoro, Fairwater, Van Dyne, Marquette, Glen Oak, and Lagoda.
This includes the following highways...
Interstate 39 between mile markers 103 and 119.
Interstate 41 between mile markers 103 and 109.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
A Severe Thunderstorm Watch remains in effect until 400 AM CDT for
south central and east central Wisconsin.
&&
LAT...LON 4390 8888 4389 8846 4394 8840 4371 8862
4373 8960 4398 8960 4398 8889
TIME...MOT...LOC 0359Z 241DEG 22KT 4389 8921
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH
KUROSKISpecial weather statement, Apr 13, 10:06 PM CST, 38 minutes before
Special Weather Statement
National Weather Service Milwaukee/Sullivan WI
1106 PM CDT Mon Apr 13 2026
WIZ056-140500-
Sauk WI-
1106 PM CDT Mon Apr 13 2026
...A STRONG THUNDERSTORM WILL IMPACT SAUK COUNTY THROUGH MIDNIGHT
CDT...
At 1105 PM CDT, Doppler radar was tracking a strong thunderstorm 10
miles southeast of La Farge, or 12 miles north of Richland Center,
moving east at 60 mph.
HAZARD...Wind gusts up to 50 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Baraboo, Reedsburg, Prairie Du Sac, Sauk City, Wisconsin Dells, Lake
Wisconsin, Lake Delton, West Baraboo, Bluffview, North Freedom,
Merrimac, La Valle, Rock Springs, Loganville, Ironton, Lime Ridge,
Devils Lake St Park, and Hill Point.
This includes the following highways...
Interstate 90/94 between mile markers 88 and 100.
U.S. Highway 12 between mile markers 213 and 223.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
A Severe Thunderstorm Watch remains in effect until 400 AM CDT for
south central Wisconsin.
&&
LAT...LON 4364 8979 4360 8976 4360 8972 4357 8973
4356 8961 4337 8961 4335 8969 4331 8973
4328 8971 4326 8973 4331 9019 4355 9019
4356 9031 4364 9031
TIME...MOT...LOC 0405Z 271DEG 51KT 4351 9044
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH
KUROSKISpecial weather statement, Apr 13, 10:31 PM CST, 13 minutes before
Special Weather Statement
National Weather Service Milwaukee/Sullivan WI
1131 PM CDT Mon Apr 13 2026
WIZ056-062-140530-
Iowa WI-Sauk WI-
1131 PM CDT Mon Apr 13 2026
...STRONG THUNDERSTORMS WILL IMPACT IOWA AND SOUTHERN SAUK COUNTIES
THROUGH 1230 AM CDT...
At 1131 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from 7 miles south of Wonewoc to 10 miles north of
Bloomington. Movement was east at 40 mph.
HAZARD...Wind gusts up to 50 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Dodgeville, Prairie Du Sac, Mineral Point, Lake Wisconsin, Spring
Green, Highland, Arena, Plain, Bluffview, Centerville, Avoca, Orion,
Linden, Cobb, Merrimac, Clyde, Governor Dodge St Park, Edmund,
Blackhawk Lake Rec Area, and London.
This includes the following highways...
U.S. Highway 18 between mile markers 49 and 50.
U.S. Highway 12 near mile marker 223.
U.S. Highway 151 between mile markers 35 and 47.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
A Severe Thunderstorm Watch remains in effect until 400 AM CDT for
south central Wisconsin.
&&
LAT...LON 4320 9043 4321 9029 4317 9019 4344 9019
4341 8960 4336 8965 4335 8969 4324 8977
4324 8980 4321 8984 4317 8984 4282 9019
4287 9043
TIME...MOT...LOC 0431Z 283DEG 35KT 4355 9018 4304 9090
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH
KUROSKINOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1329133, 1329144, 1329150, 1329140, 1329145, 1329167, 1333608, 1329166, 1329170, 1329156, 1329165, 1329169, 1329207, 1329182, 1329208, 1333692, 1329200, 1329203, 1333613, 1329204, 1329206, 1329205, 1329219, 1329168, 1329227, 1326650, 1326657, 1333562, 1326661, 1333704, 1333564, 1333594, 1333611, 1333571, 1333615, 1333593, 1333596, 1333577, 1333580, 1333584, and more.